CN-116007945-B - Experimental method and device for compression characteristics of piston pushing powder based on parallel light projection

Abstract

The invention discloses an experiment method and device for compression characteristics of piston pushing powder based on parallel light projection, wherein the experiment method comprises the following steps of arranging an optical assembly, a piston pushing powder device and a projection screen in parallel; the piston powder pushing device is provided with a shell with high light transmittance and a piston push rod assembly, powder fuel is filled in the shell, parallel light is sent through the optical assembly and passes through the piston powder pushing device, the powder fuel in the piston powder pushing device and the piston push rod assembly form projection on a projection screen, a piston rod assembly is pushed to compress the powder fuel, the volume change and the filling density change of the powder fuel are obtained according to the height change of the projection, and the compression characteristic of the powder fuel in the piston pushing process is obtained by combining thrust data of the piston rod assembly. It was used to study the powder fuel packing density response under piston pushing.

Inventors

• YANG JIANGANG
• HU YING
• HU JIAMING
• WEI RONGGANG
• LI FENGCHAO
• HU CHUNBO

Assignees

• 西北工业大学

Dates

Publication Date

20260512

Application Date

20221220

Claims (5)

1. 1. The experimental method of the compression characteristic of the piston pushing powder based on the parallel light projection is characterized by comprising the following steps: the optical component, the piston powder pushing device and the projection screen (5) are arranged in parallel, wherein the piston powder pushing device is provided with a shell with high light transmittance and a piston push rod component, and powder fuel is filled in the shell; Transmitting parallel light through the optical assembly, wherein the parallel light passes through the piston powder pushing device, and powder fuel and a piston push rod assembly in the piston powder pushing device form projection on the projection screen (5); The piston rod assembly is pushed to compress the powder fuel, and the volume change and the filling density change of the powder fuel are obtained according to the projected height change; The powder pushing device comprises a shell with high light transmittance and a piston push rod assembly, wherein the piston push rod assembly comprises a piston (11) and a cavity for placing the powder fuel, one side of the piston (11) away from the cavity is connected with a motor guide rod (15) connected with a motor (14) through a thrust detection element, and the motor (14) is used for providing power for the movement of the piston (11) to compress the powder fuel.
2. 2. The method for testing the compression characteristics of the piston push powder based on parallel light projection according to claim 1, wherein the thrust detection element comprises a connection block (12) connected with the piston (11), and the connection block (12) is connected to one end of the motor guide rod (15) through a thrust sensor (13).
3. 3. The method for testing the compression characteristics of the piston push powder based on parallel light projection according to claim 2, wherein the housing comprises a detachable upper tube (4) and a detachable lower tube (10).
4. 4. The method for testing the compression characteristics of the piston pushing powder based on parallel light projection according to claim 2, wherein the projection screen (5) is provided with grid coordinate paper (6).
5. 5. The method of testing the compression characteristics of a piston push powder based on parallel light projection according to claim 2, wherein the optical assembly comprises a convex lens (2).

Description

Experimental method and device for compression characteristics of piston pushing powder based on parallel light projection Technical Field The invention belongs to the technical field of powder engines, and particularly relates to an experimental method and device for piston pushing powder compression characteristics based on parallel light projection. Background For powder engine powder supply system, the mode that the piston pushed powder is commonly adopted in current research to realize the ration supply of powder fuel, and this mode still can fill the space that the output powder left simultaneously, guarantees that the powder fuel packing density in the storage tank is invariable. In fact, however, in order to ensure good supply and fluidization of the pulverized fuel in the tank, the pulverized fuel is generally stored in a relatively loose state in the powder tank. Therefore, when the piston is driven to supply the powdery fuel, the loose powdery fuel in the storage tank tends to be gradually compacted under the extrusion action of the piston and deviate from the initial accumulation state. However, since the flow rate of the pulverized fuel is generally designed according to the initial packing density of the pulverized fuel, the above process may cause the flow rate of the pulverized fuel to deviate from the design value during actual operation of the engine, which is disadvantageous for accurate control of the thrust force of the engine. The research on the compression characteristics of powder is mainly focused on the fields of powder metallurgy and medicine preparation, and the measurement method of a powder pressing curve does not have unified standards, and is generally measured by adopting a die pressing method. The molding method is to load powder into a mold with precise size, and then slowly press the powder in the mold by using a punch on a material mechanical testing machine, wherein the pressure is directly measured by a pressure gauge, and the density of the compressed powder compact is usually measured by adopting a combination of an in-mold method and an out-mold method. The in-mold method is obtained by using a stress-strain curve drawing device on a material mechanical testing machine, and the out-mold method is measured by a drainage method after the powder compact is demolded. The method described above uses mechanical means to apply pressure to the powder to obtain a powder compaction profile, but this is quite different from the force of a piston in a powder feed system on the powder fuel. In the powder supply system, the piston only applies a force to one side of the powder fuel, and the molding rule is two sides, in the second aspect, the molding method is usually used for pressing the powder into a block-shaped solid, and the powder engine needs to avoid compacting the powder by the piston, and in the third aspect, the existing experimental device does not have a visual function, and the influence process of the piston on the powder filling density and the change of the powder stacking profile in the pushing process cannot be obtained without interference. Therefore, the existing experimental methods cannot meet the requirements. At present, the field of powder engines also has no test method and device for researching the change of the powder filling density and the change of the stacking profile in the piston pushing process. However, the piston pushing process has a great influence on the accumulation state of the powder fuel in the powder engine supply system, which can lead to unpredictable powder filling density in the storage tank and is unfavorable for the accurate control of the thrust of the powder engine, so that an experimental method and an experimental device for researching the compression characteristic of the powder fuel in the piston pushing process are needed to be established. Disclosure of Invention The invention aims to provide an experimental method and device for compression characteristics of piston pushing powder based on parallel light projection, so as to study the response characteristics of powder fuel filling density under the action of piston pushing. The invention adopts the following technical scheme that the method for testing the compression characteristics of the piston pushing powder based on parallel light projection comprises the following steps: the optical component, the piston powder pushing device and the projection screen are arranged in parallel, wherein the piston powder pushing device is provided with a shell with high light transmittance and a piston push rod component, and powder fuel is filled in the shell; parallel light is sent through the optical component, passes through the piston powder pushing device, and powder fuel in the piston powder pushing device and the piston push rod component form projection on the projection screen; The method comprises the steps of pushing a piston rod assembly to compress powder fuel, ob